Hi i have an issue with my Classic 99 uk2000.

 

When i'm driving the car at about 3500-4000 revs the car bogs down and loses all of it's grunt.

So far i have changed the following:

Maf sensor

Cam sensor

Crank sensor

Throttleboby

Plugs and Leads

Coil Pack

Fuel tank and lines flushed

Injectors tested and refurbished

 

Now i am at a loss and cant figure out what else to do.

Any advice would be gratefully recieved.

Does it have a dump valve?

no it is standard

Does the cel come on? Have you done the error code check?

I done the error code check and got a continous flash which is no stored codes if i've read it correctly.

The engine light does'nt come on.

What grade /type fuel do you put in it?

Has it got a boost gauge if so what does it read ? As it could be fuel cut if it's over boosting.

Did you change the fuel filter and how old is your fuel pump ?

Maybe get the fuel pressure checked in case the fuel regulator or pump is getting tired .

Could always get it on a dyno for £40 and the operator might find the fault or at least narrow it down (spark ,fuel ect)

I put shell v-power in it high octane. There is no boost guage fitted.

Forgot to put in the earlier post that i had also changed the fuel filter and pump. I have changed everything mentioned above in the last three weeks.

Does it happen in straight lines or corners? Just thinking I was warned if you corner a bit strong with 1/4 tank of fuel you will get fuel surge which does feel like it hesitates for a second. Is it every gear at the same rev?

Both it only seems to happen when the car is under load as when you start the car it idles perfectly you can also take the car through the completer rev range and no coughing or spluttering as long as you are stationary.

I have spoken to the local mechanic and he thinks it could be something to do with the 02 sensor.

Sorry yes every gear same rev range.

Only at full throttle? 1/2 or 3/4 throttle up through the revs give you the same flat spot?

about 3/4 throttle if i drive easy through the revs the car will go it just doesnt throw you into your seat.

Above 3/4 throttle with give you the bogging down but below that will rev all the way up without an issue?

pretty much yes there is a slight flat but nothing like 3/4 and above.

I was thinking along the lines of overfueling.

Do you get a bit of black smoke from the exhaust?

Yes and a slight smell of petrol. Just not sure what else to try.

As savage said try to get on a dyno and have boost and afr monitered. Do you have any modifications and map on the car?

No car is completely standard thats one of the reasons i bought it.I'ts only done 82000 with a full subaru service history.

i've only had it about 6 months and it was going great up until 3 weeks ago.

Anything change just before it started to play up? Check for air leaks too. May hear a feint hissing noise.

Faulty fuel pump.put a new pump and filter on at the same time.